Winding assembly for a rolling mill

ABSTRACT

Please amend the Abstract of the Disclosure to read as follows. In accordance with 37 CFR §1.72, the abstract is submitted herewith on a separate sheet of paper, following page 6 of this amendment. 
     A winding assembly for a rolling mill for sheet metal, comprising: which includes
         a winding spool, which turns about a first axis, and wound on which is a coil (formed by a continuous sheet of metals,   An ironing roll, which turns about a second axis parallel to the first axis.   An oscillating support carries the ironing roll and is associated to actuator means, which are designed to push the ironing roll against the coil being formed.   A pass-line roll, turns about a third axis parallel to the first and second axes.   At least one deflector roll turns about a fourth axis parallel to the first, second, and third axes and is set between the pass-line roll and the ironing roll.       

     The axis of rotation of the at least one deflector roll is mobile parallel to itself, and a control unit is provided, which, in operation, adjusts continuously the position of the axis of the rotation of the deflector roll as a function of the diameter of the coil.

FIELD OF THE INVENTION

The present invention relates to a winding assembly for a rolling mill.

The invention has been developed with particular reference paid to rolling mills for rolling aluminium sheet. Rolling mills for aluminium produce sheets with a thickness ranging from 8 mm to 5 μm. Downstream of the rolling mill, the sheet is gathered in a coil by means of a winding assembly.

DESCRIPTION OF THE PRIOR ART

A winding assembly for a rolling mill for aluminium sheets generally comprises the following main components:

a winding spool, which turns about a first horizontal axis, wound on which is a coil formed by a continuous sheet of metal;

an ironing roll, which turns about a second axis parallel to the first axis;

an oscillating support, carrying the ironing roll and associated to actuator means, which are designed to push the ironing roll against the coil being formed;

a pass-line roll, which turns about a third axis parallel to the first axis and to the second axis; and

at least one deflector roll, which turns about a fourth axis parallel to the first, second, and third axes and is set between the pass-line roll and the ironing roll.

The pass-line roll is tangential to the plane of the sheet coming out of the rolling mill. In more traditional solutions, the pass-line roll is constituted by a simple roll. In more modern solutions, the pass-line roll is constituted by a flatness-measuring roll, designed to detect possible errors of flatness of the sheet immediately downstream of the rolling mill. The signals provided by the flatness-measuring roll are used for correcting the operating conditions of the rolling mill, according to a technique in itself known in the sector.

The deflector roll has the purpose of ensuring that the sheet will have a certain angle of winding with respect to the pass-line roll.

The ironing roll has the task of expelling the air between the sheet and the coil being formed. The air that remains trapped between successive layers of the coil produces major problems of flatness of the sheet and, given the same dimensions of the coil, entails a reduction in the useful weight of the coil.

The ironing roll is pressed against the coil in a point situated slightly further downstream with respect to the point of tangency between the sheet and the coil. Defined as angle of winding is the angle comprised between the radius of the coil passing through the point of tangency between the sheet and the coil and the radius of the coil passing through the point of contact between the ironing roll and the coil. The angle of winding is a very important process parameter for ensuring correct winding of the sheet on the coil.

Since the ironing roll is carried by an oscillating structure about a fixed axis, the angle of winding varies as a function of the diameter of the coil. For example, in a winding assembly of a known type, during formation of the coil, the angle of winding can vary from a minimum of 1.6° when the coil has a diameter of approximately 665 mm up to a value of 7.6° when the coil reaches dimensions in the region of 2000 mm.

This variation of the angle of winding creates considerable problems, amongst which the greater tendency to accumulate air between the layers of the coil as the diameter of the coil increases. Traditionally, formation of the coil is interrupted when, on account of the increase in the angle of winding, a regular winding of the sheet can no longer be ensured.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a winding assembly for a rolling mill that will enable the aforesaid drawbacks to be overcome. In particular, the purpose of the invention is to provide a winding assembly that will enable control and adjustment of the angle of winding during formation of the coil.

According to the present invention, this object is achieved by a winding assembly having the characteristics forming the subject of claim 1.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will now he described in detail with reference to the attached drawings, which are provided purely by way of non-limiting example and in which:

FIG. 1 is a schematic side view of a winding assembly according to the present invention associated to a rolling mill;

FIGS. 2 and 3 are side views of the winding assembly according to the present invention in the condition of minimum and maximum diameter of the coil, respectively;

FIG. 4 is a plan view of the winding assembly according to the present invention;

FIG. 5 is a cross section according to the line V-V of FIG. 3; and

FIG. 6 is a detail at a larger scale of the part designated by the arrow VI of FIG. 5.

DETAILED DESCRIPTION OF AN EMBODIMENT OF THE INVENTION

With reference to FIG. 1, the reference number 10 designates as a whole a rolling mill for aluminium sheets, comprising a sturdy framework 12 carrying a pair of rolling rolls 14 and a pair of contrast rolls 16. A continuous sheet F advances in the direction indicated by the arrow 18 and is compressed by the rolling rolls 14 that produce a reduction of thickness of the sheet F. Downstream of the rolling mill 10, a winding assembly 20 gathers the sheet F in a coil 22.

The rolling mill 10 has been illustrated in a purely schematic way merely to provide a framework for the present invention. The invention regards specifically the winding assembly 20, which can be combined with rolling mills of any type.

In FIG. 1, the coil 22 is illustrated with a solid line in the condition of minimum diameter and with a dashed line in the condition of maximum diameter. The coil 22 is wound on a spool 24, which turns about a first stationary horizontal axis 26, orthogonal to the plane of representation of FIGS. 1 to 3.

With reference in particular to FIGS. 2 and 3, the winding assembly 20 comprises a stationary base 28, fixed, for example, on the output side of the framework 12 of the rolling mill 10.

The winding assembly 20 comprises an ironing role 30, which turns about a second axis 32 parallel to the axis of rotation 26 of the spool 24. The ironing roll 30 is carried by an oscillating structure 34, which is articulated to the stationary base 28 about an axis 36 parallel to the axis of rotation 32 of the ironing roll 30.

With reference to FIG. 4, the oscillating structure 34 comprises two arms 38, which carry the ends of the ironing roll 26 in such a way that they can turn. The two arms 38 are fixed to the opposite ends of a shaft 40 articulated to the stationary base 28 about the axis 36. With reference to FIGS. 2 and 3, the two arms 38 of the oscillating structure 34 have a rocker conformation and have appendages 42, which co-operate with respective hydraulic actuators 44 articulated between the appendages 42 and the stationary base 38. The actuators 44 apply to the oscillating structure 34 a torque in the direction indicated by the arrow 46 in FIGS. 2 and 3. Said torque keeps the ironing roll 30 pressed against the coil 22.

With reference to FIGS. 2 and 3, the point of contact between the ironing roll 30 and the coil 22 is slightly displaced with respect to the point of tangency between the sheet F and the coil 22. Defined as angle of winding is the angle comprised between the radius of the coil R1 passing through the point of tangency of the sheet and the radius of the coil R2 passing through the point of contact between the ironing roll 30 and the coil 22. The point of tangency between the sheet and the coil and the point of contact between the ironing roll and the coil are defined by She intersection of the line of tangency between the sheet and the coil and between the line of contact between the ironing roll 30 and the coil 22 with a plane orthogonal to the axis of rotation 26 of the coil 22.

The winding assembly 20 comprises a pass-line roll 48 carried by the stationary base 28 in such a way that it turns about a third axis 50 parallel to the first axis 26 and the second axis 30. In the example illustrated in the figures, the pass-line roll 48 is constituted by a flatness-measuring roll. This roll is in itself known and is typically constituted by a plurality of sections set side by side (FIG. 4), each of which supplies a signal indicating the pressure applied by the sheet F. The signals supplied by the different sections of the roll 48 enable high-precision control of the flatness of the sheet F at output from the rolling mill 10. The information supplied by the flatness-measuring roll 48 is used, in a way in itself known, for adjusting the operating parameters and the conditions of operation of the rolling mill 10 so as to correct instantaneously possible errors of flatness of the sheet F. Alternatively, the pass-line roll 48 could be constituted by a simple roll.

The winding assembly 20 comprises a deflector roll 52 set, with reference to the direction of advance of the sheet F, between the pass-line roll 48 and the ironing roll 30. The deflector roll 52 turns about a fourth axis 54 parallel to the axes 26, 32 and 50. The deflector roll 52 has the purpose of deflecting the sheet F downstream of the pass-line roll 48 so as to ensure that the sheet F will have an angle of winding with respect to the pass-line roll 48.

According to the present invention, the axis of rotation 54 of the deflector roll 52 is mobile parallel to itself, and the position of said axis is adjustable as a function of the diameter of the coil 22. The adjustment of the position of the axis 54 of the deflector roll 52 enables control and adjustment of the angle of winding.

Thanks to the present invention, the angle of winding is no longer an uncontrollable parameter depending only upon the geometry of the winding assembly but becomes a parameter adjustable by varying the position of the deflector roll.

FIGS. 2 and 3 show two positions of the deflector roll 52 corresponding, respectively, to the position of minimum diameter and that of maximum diameter of the coil 22. The deflector roll 52 is displaced in a progressive and continuous way during formation of the coil 22 so as to maintain the angle of winding constant or else so as to vary the angle of winding as a function of the diameter of the coil according to a pre-set law.

The winding assembly according to the present invention could also be provided with two deflector rolls, set in series with respect to one another along the path of the sheet F. In this case, the deflector roll immediately adjacent to the pass-line roll 48, which turns about a fixed axis, would have the purpose of keeping the angle of winding of the sheet constant on the pass-line roll 48, whilst the deflector roll 52 immediately adjacent to the ironing roll 32 would be mobile for controlling the angle of winding.

In what follows, an adjustment mechanism will be described For adjusting the position of the deflector roll 52 during formation of the coil 22. It is understood, however, that the present invention is not limited to this particular adjustment mechanism, it being possible to use various other systems for adjusting the position of the deflector roll.

With reference to FIGS. 4, 5 and 6, the deflector roll 52 is carried in such a way that it turns about its axis of rotation 54 by a pair of end bearings 56. The bearings 56 are carried by two slides 58 that slidingly engage respective guides 60 fixed with respect to the stationary base 28. The guides 60 are rectilinear and orthogonal with respect to the axis of rotation 54 of the deflector roll 52. Preferably, the guides 60 extend in a vertical direction.

Preferably fixed to one of the two slides 58 is a flange 62 carrying an electric motor 64, which drives the deflector roll 52 in rotation about the axis of rotation 54 by means of a belt transmission 66. The two slides 58 are fixed to one another by means of a cross-member 68 that is associated to an actuation device 70.

The actuation device 70 comprises an electric motor 72 numerically controlled by an electronic control unit 74, which, among other things, receives information regarding the diameter of the coil 22 being formed. The motor 72 is connected to two transmission devices 76 carried by a fixed beam 78. The two transmission devices 76 convert the rotary movement imparted by the motor 72 into a linear movement of respective output members 80 connected to the cross-member 68. The two transmission devices 76 are connected together by means of a shaft 82.

Preferably, the actuation device 70 is moreover provided with a stabilization mechanism designed to guarantee that the cross-member 68 moves remaining always parallel to itself. Said stabilization mechanism can be obtained by means of a pair of rack devices 86 including respective racks 87 fixed to the cross-member 68. The two rack devices 86 are provided with respective toothed gears that are fixed to one another by means of a tubular shaft 88 set coaxially on the outside with respect to the shaft 82 that connects the actuation devices 76 to one another.

In operation, the electronic control unit 74 controls the electric motor 72 as a function of the diameter of the coil 22. The actuation device 70 controls the movement of the deflector roll 72 in the direction indicated by the arrow 90 in FIG. 5. As the diameter of the coil 22 increases, the deflector roll 52 displaces parallel to itself, with a speed of movement correlated to the speed with which the diameter of the coil 22 increases.

From a comparison between FIGS. 2 and 3, it may be noted that the displacement of the deflector roll 52 enables control of the angle of winding (defined as the angle between the radii R1, R2 of the coil 22). The angle of winding can be kept constant or else can be varied with a pre-set law as a function of the diameter of the coil 22. 

1. A winding spool, which turns about a first axis, wound on which is a coil formed by a continuous sheet of metal comprising: a winding spool, which turns about a first axis, wound on which is a coil formed by a continuous sheet of metal; an ironing roll, which turns about a second axis parallel to the first axis; an oscillating support, carrying said ironing roll and associated to actuator means, which are designed to push the ironing roll against the coil being formed; a pass-line roll, which turns about a third axis parallel to the first and second axes; and at least one deflector roll, which turns about a fourth axis parallel to said first, second, and third axes and is set between the pass-line roll and the ironing roll, wherein the axis of rotation of said at least one deflector roll is mobile from a first position to a second position parallel to itself said first position and wherein a control unit is provided, which, in operation, adjusts continuously the position of the axis of rotation of the at least one deflector roll as a function of the diameter of the coil.
 2. The winding assembly according to claim 1, wherein the deflector roll is provided with end bearings carried by slides mobile along stationary linear guides.
 3. The winding assembly according to claim 2, wherein said slides are connected together by a cross-member associated to a control device operating under the control of said control unit.
 4. The winding assembly according to claim 3, wherein said control device comprises a numerically controlled electric motor and a pair of transmission devices with linearly mobile output members associated to said cross member.
 5. The winding assembly according to claim 3, wherein said control device comprises a stabilization mechanism including two rack devices associated to said cross-member and connected together by means of a shaft. 